After you read these note, it is important for you to go to
this link Chemical
and Physical Properties & Changes w practice quiz .Read the additional background material on
physical and chemical properties and answer the practice questions.When you get to the bottom of this page, take
the link there to learn about different types of matter, and take the
practice quizzes there to check your understanding.

Physical
Properties ­

Properties of an element or a compound
that can be observed without a chemical reaction. These include:

mass

volume

density

color

odor

shape

melting
point

boiling
point

state
(solid, liquid, gas)

The state can be changed, but the
substance will still be the same when you return to the original state.

Example
 We think of water as only being the liquid state.Actually water can be a solid which we call
ice.Water can also be a gas, which we
call steam.Steam can be condensed to
form liquid water and ice can be melted to form liquid water.Water in any state is still water,
specifically H2O.

hardness

softness

Chemical Properties 

Properties of
an element or compound can will be observed when a
chemical reaction occurs.Examples ofchemical
properties could be:

1.how
sulfuric acid reacts with sugar

2.how
electricity reacts with water to form hydrogen and oxygen

3.how
magnesium reacts with water to form magnesium oxide

Physical Change 

The stubstance(s) involved in physical changes are not changed
chemically in physical changes.They may
change state (solid to liquid to gas) or they may be separated or mixed.However, they can always be seaparated or changed back to their original state.Examples are:

1.water is frozen or evaporated (changed to ice or to steam)

2.a piece of paper is torn in two

3.a diamond is used to cut a ruby

4.salt dissolves in water, when the salt water is evaporated
the salt is left behind

5.two different colored paints are mixed to form a new color
that is different from either of the original colors

6.acetone evaporates rapidly at room temperature

Chemical Change 

Two substances
(reactants) react with each other and one or more new substance(s)
(products) are created that is/are different from the original
substance(s).Products and reacts have different
physical properties.Examples are:

1.when sulfuric acid
(H2SO4) reacts with sugar (C12H22O11)
and forms carbon (C) and water (H2O) reactants and products are very
different in both chemical and physical properties

3.when electricity is
passed through water (H2O) two new substances are formed, hydrogen
(H2) and oxygen (O2)

TYPES OF
MATTER

Pure Substances 

Constant defined composition and cannot be separated into simpler
substances by physical means.There are
two types of Pure Substances:

Elements  Are pure substances
made out of only one kind of atom.The
periodic table contains all the known elements.

Compounds  Pure substances that
are made of two or more different atoms.These substances follow the law of constant
composition.That means that there
is a set ratio of each atom in the compound to every other atom in the compound
( i.e. H2O ) .These substances can be broken down by
chemical means into the atoms that make them up.However, they cannot be separated by physical
means.

Mixtures 

These
substances are made up of more than one elementand / orcompound.Different mixtures can
be almost any proportion of one element or compound to another.A good visualization of this can be seen at Elemnt,
cmpd, mix (molecular
level w MDL models you can rotate)- applets (you will need Chime to view this, see
instructions on the home page for how to do get a free download).Salt water is a good example of a
mixture.You could have 15% NaCl and 85%
H2O, while another mixture could have 70% NaCl and 30% H2O.The two types of mixtures are:

Homogeneous mixtures  There is
the same composition of elementsand /
orcompounds everywhere.So, homogeneous mixtures are exactly the same
everywhere.When a substance dissolves
in water (like salt water) it will be homogeneous.

Heterogeneous mixtures 
Substances in heterogeneous mixtures are not evenly distributed.Try to visualize sand and rocks in
water.The sand and rocks will be at the
bottom, while the water will be above.The sand will tend to settle under the rocks and between them.